Someone recently challenged me to debate the existence of climate change. Debates are extremely useful for discussing matters that require value judgements. But pointless for establishing what is true of the physical world – for that you need the scientific process. In a complex field like climate change, the best approach is a systematic assessment of the scientific literature.

Debates are won or lost on the rhetorical skills of the debaters. If we were to debate the science of climate change, the set up is somewhat stacked against scientists. Scientists are obliged to stick to the evidence, deal honestly with the uncertainties, and attempt to show how the many different lines of evidence give us confidence in our understanding of climate systems. Scientists eschew rhetoric. Those who want to attack the science need only throw enough talking points around to sow doubt in the minds of the audience. They have at their disposal rhetorical tricks like the gish gallop. The entire exercise is pointless.

Now, if someone wants to debate, say the ethics of leaving subsequent generations to clean up our polluting ways, I’m all on it. That’s a matter of value judgement. If anyone wants to debate the existence or seriousness of anthropogenic climate change, I’d give the same response as I would if they wanted to debate the existence or strength of gravity.